In Applicant's WO 01/52558 A2 entitled “Method for Operating a Cellular Telecommunications Network, and Method for Operating a Personal Cellular Telecommunications Device” and WO 01/52572 A1 entitled “Method for Operating a Cellular Telecommunications Network”, the contents of which are incorporated herein by reference, there is illustrated and described a screen saver application for displaying display messages on personal cellular telecommunications devices in a screen saver like manner, namely, their display is temporarily interrupted during, say, a voice call, an Internet session, and the like. The display messages are preferably so-called “interactive display messages” in the sense that a subscriber can automatically activate a Point-To-Point (PTP) transmission response mechanism from a dedicated response means integrally provided in a display message. Interactive display messages are preferably transmitted over a Point-To-MultiPoint (PTMP) transmission capability as opposed to over a PTP transmission capability, thereby rendering an interactive cellular broadcasting service.
ETSI's GSM 03.41 standard entitled “Technical Realization of Cellular Broadcast Service”, the contents of which are incorporated herein by reference, standardizes a so-called “macromessage” constituted by between one and 15 broadcast messages each having a 82 byte payload for transporting long display messages of up to a maximum of 1230 bytes. This upper limit of 15 broadcast messages is due to the provisioning of only 4 bits for the purpose of specifying the number of pages in a macromessage i.e. 1111. Despite the inclusion of the macromessage feature since the inception of the GSM 03.41 standard, neither do many installed GSM Cell Broadcast Controllers (CBCs) employed for parsing an display message into broadcast messages support the macromessage feature, nor do many Base Station Controllers (BSCs) for transmitting the broadcast messages and nor do many GSM personal cellular telecommunications devices. Looking to the future, assuming that all installed CBCs, BSCs and devices support the macromessage capability, the maximum 1230 byte payload of a macromessage may be insufficient to transport certain bandwidth heavy display messages, for example, including video content.